Street sweeper



May 22, 1923. A 1,456,393 'Y E. R. MARTIN Filed March so, 1921 v 2 sham-sheet 2 gw 4/ www@ Patented May 22, i923.

U HT E S T fl S ELMER R. MARTIN, 0F ELGIN, ILLINOIS, ASSIGNOR TO ELGIN STREET SWEEPER C0.,

' OF ELGIN, ILLINOIS'A COPARTNERSHIP.

STREET SVEEPER.

Application led March 30, 1921.

To all whom 'it may concern.'

Be it known that I, ELMER R. MARTIN, citizen of the United States, residing at Elgin, in the county of Kane and State of Illinois, have invented cert-ain new and useful Improvements in a Street Sweeper; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to a pick-up street sweeping machine of the general class having a rotary broom arranged for sweeping dirt and other refuse off the surface of the street and having an inclined conveyer disposed `for conveying the sweepings to a suitable hopper. In sweepers of this class, it is necessary to have the lower end of the conveyer proper (or the lower end of the casing which houses this conveyer) raised stifliciently above the surface of the street to pei mit ordinary accumulations ofv refuse, fallen leaves or the like to pass under the same into the path of the broom. lilith the.

constructions heretofore employed, this vertical spacing has introduced a gapl of such height that the rotating broom would project a `large share of the sweepings directly through this gap unless the gap was kept closed by a suitable dirt pan or shoe,

For this purpose, it has been'customary to employ a dirt pan or shoe pivoted to the conveyer casing and dragging at an incline behind this casing and immediately in front of the broom, and it has also been customary to mount this dirt pan or shoe so close to the broom that it would act as a deiiector for deflect-ing and guiding the broom-projected sweepings to the conveyer, leaving any sticky accumulations of refuse to be swept off the dirt pan by the broom. In practice, this arrangement has shown a number of serious disadvantages, one being the fact that the dragging dirt pan will tend to slide loose refuse ahead of it, thereby keeping this refuse effectively out of the path of the broom and particularly preventing the sweeping up of such light objects as loose papers or dry leaves. Another objection has been the lifting of the dragging dirt ypan by stones, bunches of leaves or the like, thereby permitting a ready projection of refuse under the same by the broom and annulling the effectiveness of the dirt pan whenever serial No. 456,992(

such objects are encountered on the street. Likewise, the engagement of the dragging dirt pan with stones, masses of leaves or an7 thick accumulations of refuse often raises such a. dirt pan suiiiciently to cause the latter to bear against the broom, thereby causing undue wear on both the broom and the dirt pan while at the same time interrupting with the proper function of the dirt pan in confining sweepings to a path directed towardsA the conveyer.

Furthermore, if the machine is backed for any reason without first having the conveyer frame raised so as to lift the dragging dirt pan entirely clear of the street, or if the machine slipped back by gravity when stopped on an upward slope, the inclination of the dirt pan might cause the latter to dig into the pavement, thereby seriously damaging the latter. Moreover, stones or other heavy objects are apt to drop between the dirt pan and the lower end of the conveyer (or even between the top of the conveyer and the bottom of the conveyercasing), thereby getting jammed between the conveyer and this casing bottom; This jamming often loosens the slats on the conveyer, or bends and damages either these slats or the casing bottom, thereby interfering with the efficient operation of the machine and increasing the upkeep costs.

My invention aims to overcome all of thesecbjections and todo so vby providing an exceedingly simple construction andone which will alsofreduceboth the initial costu of construction and the cost of upkeep of the machine. More particularly, my invention aims to provide a sweeping machine of this class with a pick-up mechanism so arranged that almost all of the sweepings will be projected 'directly by the broomupon the upwardly moving stretch of the conveyer, thereby eliminating the interposinoof adirt pan for Guiding the bulk of the sweepings after they have been projected by the broom and consequently eliminating the objections which are encountered when such a shoe or dirt pan extends in front of the major por- Cil tion of the bottom of the broom. Furthermounted shoes disposed adjacent to the opposite sides of the broom and the conveyer casing, aims to provide a simple inexpensive construction and mounting for such shoes, and aims to provide simple and edective means for preventing such shoes from damaging the pavement in case the machine is backed without having the shoes deliberately raised out of their normal operative positions. It also aims to provide a dirt conveying arrangement which will not allow any damage to be done by stones or the like if these drop in front of the conveyer or if they dribble down behind the conveyer in case the hopper is overfilled. Moreover, my invention aims to provide a. broom and conveyer arrangement which will Jermit the broom to clear itself of dirt atl all times and which will not cause refuse to be carried back over the broom. Still further and more detailed objects will appear from the following specification and from the accompanying drawings, in which Fig. 1 is a fragmentary side elevation of a sweeping machine embodying my invention.

Fig. 2 is an enlarged perspective view of one of the pivoted dirt pans or shoes, namely the one used at the opposite side of the machine from that shown in Fig. 1.

Fig. 3 is an enlarged and fragmentary vertical section taken along the correspondingly numbered line in Fig. and showing the normal range of the directprojection of the sweepings upon the conveyer by the broom.

Fig. 4 is a plan view of the rear end of the side plates and of the guard plates attached thereto, with the broom indicated only in dotted lines, showing the clearance between the shoes and under the conveyer casing.

Fig. 5 is an enlarged and fragmentary transverse section through portions of the side flange of a' shoe and of the broom, showing the function of the shoe.

In the illustrated embodiment, I am showing invention as applied to the street sweeping machine of the general type of the one shown in U. S. Patent No. 1239293 of Dept. 4, 1917 to J. M. Murphy, although I do not wish to be limited to this application of the same. Moreover, if the refuse is sticky, the closely placed dirt pan will force some of it between the fibers of the broom so that this portion of the refuse will be carried up over the broom, thus preventing the broom from properly clearing itself and also reducing its street-sweeping effectiveness by binding the fiber so that they cannot snap independently.

In the construction of my presentr improvement, I mount the broom at a so much greater distance behind the drum 7 about which the lower end of the conveyer is trained that the broom will project substantially all of the sweepings above a plane passing through the axis of the drum 7 and tangential of the drum, or in the example of Fig. 3 within angles of from twenty to forty degrees above the street level. By so doing, I enable the conveyer to receive the sweepings direct from the broom, thereby eliminating the necessity of employing an intervening deflector or dirt pagn. I also eliminate the necessity of continuing the conveyer casing rearwardly under the lower guide drum 7, as the relocation of the drum with respect to the conveyer practically eliminates the dropping of refuse behind the conveyor and therefore makes it unnecessary to employ a'casing portion underhanging the conveyer. Instead, I only need to employ a relatively narrow guard 8 for guarding the lower end of the conveyer against contact with stones or other tall articles which may happen to be in the path of the machine.

However, while such a direct sweeping of the refuse from the street surface to the conveyer is feasible for the major portion of the length of the drum, it is not entirely feasible for the two end portions of the broom on account of the angles at which the fibers of the broom may strike various particles or refuse. In practice, such brooms are commonly made with fibers 19 of bamboo or the like, having a more or less rounded cross-section as shown somewhat diagrammatically in Fig. 6. With the machine 'moving in the direction upwardly of that figure, it will be obvious that various particles of dirt will be deflected or projected by the different fibers of the broom in `various directions laterally of the pat-h of the broom.

Some of the particles of dirt as thus angularly projected from various fibers will impinge against each other and help to guide each other in directions longitudinally of the machine, so that the effect of the broom for the major port-ion of its length will be substantially thev same as if it were made up of fiat flaps radial of the axis of the broom. However, particles of dirt projected at angles outwardly of the machine by the fibers near either end of the broom will not be impinged by other particles correspondingly projected in the opposite direction and this portion of the sweepings would therefore be projected laterally behind the adjacent edge of the conveyer. In other words, while my relocating of the broom as indicated in Fig. 3 will effectually cause the sweepings to be directed at upward angles sufficient for projecting above the axis of the drum 7, portions of these sweepings would diverge laterally behind the conveyer and hence would not be advanced by the latter unless some special provision is made with this in mind. F or that purpose, I equip my machine with deflectors arranged for intercepting those portions of the sweepings which are directed laterally outward of the machine beyond the conveyer and for cooperating with the broom in guiding these portions to the conveyer, in doing which I desirably employ a pairof drag shoes disposed respectively adjacent to opposite ends of the broom and each having a side flange overhanging one of the side plates of the conveyer casing. Each of these shoes also has a base plate fastened to its said side flange, which base plate desirably consists of a rear portion 11 concaved to clear the broom more readily in case the shoe is lifted off the ground, and a flat portion 12 disposed in forward continuation of this concaved rear portion. rI`he side ange may desirably be fastened to the base plate of the shoe by an angle piece 13 and the rear of the base plate may be curved upon itself to encircle a 4pivot rod 14 extending transversely of the machine between the side `plates 10. The base portion of each shoe kdesirably is quite narrow in proportion to the length of the broom, as shown in Fig. 5, thus leaving a clear opening under the broom for the major portion of the length of the latter and only providing a sufficient width of base plate for the shoe to catch such particles of refuse as might tend to drop in front of the conveyer after being projected against the side flange 9 by the broom.

To keep each of the shoes from sliding along the pivot rod 14, I suitably interlock it with the adjacent side plate l0 of the conveyer casing, as by mounting a finger 15 on the outside of the side flange of the shoe, so that this linger will cooperate with a portion of the side flange in straddling an edge portion of the adjacent side plate 10 as shown in Figs. 1 and 5.

IVith the street sweeper thus arranged, it will be obvious from the above that the relatively short width of the shoes will leave almost the entire opening forward of the broom and below the guard 8 freely open for the passage of dirt, dry leaves or the like, and in practice this opening can be left even tall enough to clear an ordinary brick. Should any such object be encountered by either of the shoes, the pivotal or movable mount-ing of the latter will lift the latter, so as to clear the object without interfering with the operation of the major portionof the broom, thereby permitting the sweeper to be operated quite efficiently even under conditions where surface projections are encountered. is tallerthan the distance between the guard S and the street, the pivotal ,mounting of the entire conveyer and conveyer casing on the upper shaft of the conveyer (as shown in Fig, will permit this casing to be Or, if the encountered objectk dirt as is found ahead of a machine on a street that needs cleaning will in itself tend to form a dam and to upwardly deflect such trifling portions of the sweepings as might be directed by the broom below the conveyer, so that the actual forward projection of sweepings through this opening is negligible. Since the broom is freely spaced for a considerable distance horizontally from the bottomfof the conveyer, any refuse tending to stick to the broom will be tossed off the libers by centrifugal force and projected upon the conveyer, instead of being wedged between these fibers 'by the dirt pan after the manner of the older practice as shown in Fig. 4. Likewise, any stones or other relatively heavy objects, if not projected upon the conveyer, will merely fall through the clear opening behind the lower end of the latter, where they cannot or do any damage. Or, if the hopper overflows, any refuse dribbling from the same or surplus carried over the top of the conveyer by the latter will merely fall in front of the conveyer and of the guard 8 without having a chance to do any damage.

To permit the `ready backing of the machine as a whole, or the corresponding backing of either side of the same when the Inachine is making a sharp turn, I desirably provide means for automatically raising each shoe oftl the surface of the street when thus moved backwards. For this purpose, I am showing a side flange of each shoe as having a lever 16 pivoted to the same, which lever normally slopes downward towards the rear of the machine and drags its lower end upon the street surface. If the machine is backed, the friction of the rear end of this lever against the ground will cause the lever to tip up to a vertical position, or until it engages a stop 17, thereby rocking the shoe about its pivotal mounting so as to lift it off the surface of the street.

However', while I have illustrated and described my invention in a highly desirable embodiment, I do not wish to be limited to the details of the construction and arrangement thus disclosed, it being obvious that they might be modified in many ways without departing from the spirit of my invention or from the appended claims.

l. A ystreet sweeping machine including an inclined conveyer for advancing the .sweepings after they have been picked up,

the lower end of the conveyer being spaced from the street by a sufficient distance to clear ordinary accumulations on the latter, and a rotary broom so disposed with respect to the conveyer as to project substantially all of its sweepings directly upon the up? wardly moving surface of the conveyer, and a conveyer casing having sides connected by a relatively narrow guard forwardly of the lower end of the conveyer but otherwise open at its bottom, the guard sloping upward forwardly of the machine and the casing being pivotally supported near its upper end.

Lv. In a street sweeping machine having a rotating broom disposed for sweeping refuse directly upon an inclined conveyer and having the lower end of the conveyer spaced from the street, a pair of shoes carried by the conveyer mounting and sloping downwardly towards the broom and respectively underhanging relatively short end portions of the broom and each having a side plate extending alongside the adjacent end of the broom, the said shoes being supported to permit lifting movement thereof.

3. A sweepings confining shoe for use with the inclined conveyer of a streetsweeper having a rotary broom, comprising a movably mounted dirt pan sloping downwardly under the broom and of relatively short width with respect to the length of the broom, and aside plate fast upon the dirt pan and projecting alongside one end of the broom.

1. A sweepings confining shoe for use with the inclined conveyer of a street sweeper having a rotary broom, comprising a movably mounted dirt pan sloping` downwardly under the broom and of relatively short width with respect to the length of the broom, a side plate fast upon the dirt pan and projecting alongside one end of the broom, and means for lifting the shoe upon a backing of the street sweeper.

In a street sweeper, the combination with a movably mounted dirt pan sloping downward toward the rear of the sweeper and normally dragging upon the street, of means for automatically raising the dirt pan oil the street when the sweeper is moved backwards.

G. In a street sweeper having an upward- .y inclined conveyer in front of a rotating broom and side plates laterally housthe lower end of the conveyer, a rod spanning? the id side plates adjacent to the lower end the conveyer, apa-ir of dirt pans both pivoted upon the rod, and dragging upon the street, and means connecting each dirt pan with the adjacent side plate for preventing the dirt pan from sliding along the rod.

7. In a street sweeper having an upwardly inclined conveyer in front of a rotating broom and having side plates laterally housing the lower end of the conveyer, a rod spanning the said plates adjacent to the lower end of the conveyer, a pair of dirt pans both pivoted upon the rod and dragging on the street, and separate means on the two dirt pans for rocking each thereof on its pivotal mounting to lift it out of contact with the street upon arearward movement of the said pivotal mounting.

8. In a street sweeper7 the combination with an inclined conveyer laterally housed by side plates, ofy a. normally dragging dirt pan adjacent to one end thereof and pivoted on an axis transverse of the side plates, and an arm fast on the dirt pan and overhang ing the adjacent side plate to maintain the dirt pan close to the latter.

l). In a street sweeper having a pick-up mechanism including a rota-ting broom, a dirt pan movably supported atits forward end and sloping from the latter downwardly towards the broom and dragging with its rear end upon street surface, and a lever associated with the dirt pan and arranged for raising the latter' out of contact with the street upon a rearward movement of the dirt pan.

l0. In a street sweeper, a conveyer sloping down rearwardly and including an endless member and two revoluble members disposed at different heights and over which the endless member is trained, the lower of the two revoluble members being at a sufficient height above the street to clear ordinary accumulations of refuse on the street, a rotating broom mounted for engaging the street surface and having its axis parallel to that of the said lower revoluble member, the broom being at such a distance behind the 'conveyer as to project substantiallyv all of its sweepings above the axis of the said lower revoluble member, a pair of deliectors respectively disposed at opposite sides of the lower end of the conveyer and under hanging the broom for relatively short distances towards each other, the said deflectors being formed for intercepting sweepings projected by the broom in directions out wardly beyond the lateral edges of the conveyer and for guiding such sweepings to the conveyer, each of the deilectors dragging normally upon the streetand mounted independent of the other to permit it to follow the contour of the street.

1l. In a street sweeper, a conveyer sloping down rearwardly and including an endlessmember and two revolublmembers disposed at different heights and over which the endless member is trained, the lower of the two revoluble members being at a sufficient height above the street to'A clear ordinary accumulations of refuse on the street, a rotating broom mounted for engaging the street surface and having its axis parallel to that of the said lower revoluble member, the broom being at such a distance behind the conveyer as to project substantially all of its sweepings above the axis of the said lower revoluble member, a pair of deflectors respectively disposed at opposite sides of the lower end of the conveyer and underhanging the broom for relatively short distances towards each other, the said defleotors being formed for intereepting sweepings projected by the broom in directions outwardly beyond the lateral edges of the conveyer and for guiding such sweepings to the eonveyer, each of the delectors dragging normally upon the street and mounted independent of the other to permit it to follow the contour of the street, and means upon each deileetor and operable by a rearward movement thereof for raising the same off the street.

Signed at Elgin, Illinois, March 24, 1921. 15

ELMER R. MARTIN. 

